Method for detecting pesticide residues in tea by using gas chromatograph-mass spectrometry

A technology of pesticide residues and combined technology, which is applied in the direction of measuring devices, instruments, scientific instruments, etc., can solve the problems of few types of pesticide residues and inaccurate pesticide residues, and achieve good purification effect

Inactive Publication Date: 2014-06-25
HUAZHONG AGRI UNIV
View PDF3 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] The purpose of the present invention is to provide a method for detecting pesticide residues in tea with gas-phase mass spectrometry, which mainly solves the problem that the existing detection methods are not accurate enough to detect pesticide residues and the types of pesticide residues detected are less

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for detecting pesticide residues in tea by using gas chromatograph-mass spectrometry
  • Method for detecting pesticide residues in tea by using gas chromatograph-mass spectrometry
  • Method for detecting pesticide residues in tea by using gas chromatograph-mass spectrometry

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach

[0021] (1) Configure standard stock solution:

[0022] Accurately weigh about 0.0100g of standard substance of each pesticide, add it into a 10mL volumetric flask, dissolve with acetone and adjust the volume to the mark, and prepare a standard stock solution with a concentration of 1000mg / L of each pesticide, and refrigerate for later use.

[0023] (2) Configure mixed standard working solution:

[0024] The standard stock solution of each pesticide was taken out and placed in a 100mL volumetric flask to prepare a mixed standard working solution with a concentration of 10mg / L, and refrigerated for later use. The period of use is 1 month.

[0025] (3) Set instrument parameters:

[0026] Gas phase-mass spectrometer matching autosampler parameter settings are as follows: Shimadzu AOC-20i+S, inlet temperature 250.0°C, injection volume 1uL, splitless injection; carrier gas: high-purity helium , initial pressure 500-900Pa, linear velocity 36.8cm / sec, purge volume 6.0mL / min; capill...

Embodiment 1

[0049] Experimental materials: Standard pesticide residues were purchased from DrEhrenstorfer GmbH. Acetone, n-hexane, acetonitrile and ethyl acetate used for HPLC were purchased from J.T.Baker Company.

[0050] Concrete preparation steps are as follows:

[0051] (1) Prepare standard stock solution: Accurately weigh 0.0100g of standard product of each pesticide, add it into a 10mL volumetric flask, dissolve with acetone and set the volume to the mark, and prepare 1000mg / L standard stock solution of each pesticide respectively, Refrigerate until ready to use.

[0052] (2) Prepare the mixed standard working solution: according to the concentration of the standard stock solution of each pesticide, pipette a certain amount of the pesticide stock solution into a 100mL volumetric flask, and prepare a mixed standard working solution with a concentration of 10mg / L. Refrigerate until ready to use. When used, it is prepared into mixed standard working solutions of different concentra...

Embodiment 2

[0058] The recovery rate and precision experiment of the detection method:

[0059] Accurately weigh 3 parts of 5g crushed blank green tea matrix into a 50mL centrifuge tube, add 5uL, 25uL, 50uL of mixed standard solution respectively, and let stand for absorption. Another blank control was used for gas phase-mass spectrometry analysis. Agilent data processing system was used to automatically generate a standard curve based on peak area (Y) versus mass concentration (X), and the detection limit of the method was calculated by three times the signal-to-noise ratio. Accurately weigh 5g of crushed blank tea leaves in a 50mL centrifuge tube, add 10mL of secondary water to soak, add 50mL of 1:4 acetone: n-hexane as extraction solvent, 30°C water bath, ultrasonic at 100hz for 60min, fully shake , add a sufficient amount of sodium chloride to promote stratification, centrifuge, take the supernatant in 250mL pear-shaped bottles, and rotate under reduced pressure in a 40°C water bath....

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for detecting pesticide residues in tea by using gas chromatograph-mass spectrometry. The method comprises the following steps: preparing 109 types of pesticide samples into a mixed standard working solution; setting parameters of an automatic gas chromatograph-mass spectrometer fitted sampler; generating standard curve models of 109 types of pesticides in the gas chromatograph-mass spectrometer; putting crushed tea matrixes to be detected in a centrifugal tube to prepare a solution containing tea pesticide residues to be detected; analyzing the solution containing the tea pesticide residues obtained in the step 6 according to the parameters of the gas chromatograph-mass spectrometer set in the step 2 and the standard curve models of 109 types of pesticides generated in the gas chromatograph-mass spectrometer in the step 3 to obtain detection results. The method is capable of detecting up to 109 types of tea pesticide residues. Compared with the prior art, the method is excellent and accurate in purification effect.

Description

technical field [0001] The invention belongs to the technical field of tea pesticide residue detection, and relates to a method for detecting pesticide residues in tea leaves by gas phase mass spectrometry. Background technique [0002] Tea is a worldwide drink, but the problem of pesticide residues in tea seriously threatens human health. In order to meet the actual needs, it is necessary to establish a rapid, efficient, and low detection limit detection method for the detection of pesticide residues in tea. [0003] At present, there are still relatively few methods for the simultaneous determination of multiple pesticide residues in tea. The standards of Japan and the European Union do not provide a method for the simultaneous detection of multiple pesticide residues in tea. Most of the reported detection methods for multiple pesticide residues are the detection of a certain type of pesticides (such as organophosphates, organochlorines, carbamates, pyrethroids, etc.), a...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N30/02G01N35/10
Inventor 王鲁峰徐婷潘思轶徐晓云
Owner HUAZHONG AGRI UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products